The animal resource diagnostic laboratory has been established to serve research animal facilities at the University of Oklahoma Health Sciences Center, the Oklahoma Medical Research Foundation, the Oklahoma City V.A. Hospital and the University of Oklahoma Norman campus. The principal investigator and the coinvestigator serve the four institutions as either the director of animal research facilities or as a veterinary medical consultant. A close association therefore exists between the diagnostic laboratory and the animal health programs at these institutions. The animal health programs benefit through improved capability for detecting, diagnosing, treating and preventing disease in the animal colonies. Procedures employed include necropsy, histopathology, serology, hematology, microbiology and chemistry. The diagnostic laboratory has been useful in developing new or improved animal models for biomedical research. Information provided during the preliminary phases of investigation have guided investigators in refinements of experimental techniques. The institutions also benefit from the collection of pathological material which will be used in providing training in comparative pathology.